Camper Shell / Tailgate Weatherproofing

I'm hoping to rejuvenate the topper on my (new to me) rig. It's been on the truck since 2005 so naturally it could use some TLC.
I drove on the highway a few weeks back during a thunderstorm and noticed a small amount of water in the front corners of the bed and I have plans to build out a bed platform, so I want to seal this bad boy up nice for some late summer / fall camping trips.
While I have the topper off, I also want to insulate and line the topper like this TW member: https://www.tacomaworld.com/threads/camper-shell-build.476020/

These items are what I'm looking to order, and will be picking up the carpet/insulation/adhesive locally.

Bulb seal:

$40 ESI Ultra Cap Seal 1 1/2" Width x 5/8" Height x 23' Length, EPDM Rubber for Caps Over 200 lbs

https://www.amazon.com/gp/product/B00MPMBIZW/ref=ox_sc_act_title_1?smid=A26GQRWSJVLGWV&psc=1

Tailgate seal:

$28 ESI Ultimate Tailgate Seal with Taper Seal 10ft for use with Truck Caps and Tonneau Covers

https://www.amazon.com/Ultimate-Tailgate-Seal-Taper-10ft/dp/B00IPQWXZQ

My questions for you fine folks are:
1) Any tips for removing/cleaning/resealing my topper?
I have a feeling the old seal is gonna be a b&*$h to remove and to clean off the bed
2) Has anyone installed a tailgate seal?
I dont have a bed liner, just a bed mat. It seems pretty straightforward but personal recommendations are always appreciated.

Here are some pics of the bed, you can see the light coming through on the front corners.


Thanks!

 

Oh and for posterity, here is my truck from this weekend. Did a little beaching and camping in RI/Cape Cod:

 

I can tell you I bought the same "double bulb" and other material and I didn't work for me. It helped a little but still leaks. I also put pipe insulation along the front rail.

I will add that the main reason mine leaks is because it was made for a double cab and it's an old topper.

 

Load’er up with some Fuze by Liquid Nails and she’ll be submarine material. Gett’r dunn.

 

Ha! Fortunately I don't need it to be submersible and I'd like to take it off if needed.

 

I also did that and it did not work. Some shells just leak. These things aren't air tight. The windows leak too.

 

I think the trick will be to eliminate any and all cuts to the weatherstripping...particularly in the corners. I had leaks on my T100 topper and I think it was because I had the seals cut and just touching in each corner. If you can run one continuous line of the seal and work it around the corners it should work ok. Then maybe an extra clamp as close to the corners as possible.

Oh, and if you're camping in it, the universal BedRug mat could be a great addition. You'll have to cut to fit, but should be comfy. I have one that I still need to cut.

 

Great tips, thank you sir!

Gotcha. I'm definitely scared of taking the windows out to do the carpeting because they don't leak right now. The PO took really good care of it. I don't need air tight but definitely don't want my gear and bed getting soaked in a storm.

 

Update time!

Redid the seal with double bulb and a large bed rail seal on the front. The clamps really squeezed the seal together and so far, no leaks!


Truck looks weird without a cap..


Now time to build bed platform. I did a good amount of research on designs and landed on a pretty basic two box setup with flip tops for storage, aka "carpet kit". I need the ability to throw mountain bikes and go into "pickup" mode quickly if needed. The height is based on a YETI cooler.

Basically I bought two sheets of 1/2" ply and some 2x3's, and had some scrap 2x4s. Didn't necessarily have a plan but put together the frames in one night. The lengths are notched around my clamps.


Next up, squaring up the frames. Due to wonky scraps (or bad craftsmanship) the frames weren't exactly square. We came up with a ratchet strap securing/squaring system. The straps are wrapped around the cargo tie downs and tightened, which will help with squaring and install/removal making everything tight and tidy.





Plywood walls..



Almost finished. Next up is piano hinges, two piece center platform with marine carpet. Thanks for reading!