So I've further developed the gas spring "helper-spring" replacement design.....
Here are a couple shots of the config I've been running since 2018.......as discussed in the posts above in this thread.
This design works quite well, but I wanted to get the compressed spring stack load off of the rear of the PH roof channels and transfer that load into a plate/mounting bracket that covers the springs.
I have wanted to further increase the spring load at the end of roof travel when the roof is down, but didn't want to risk bending sheet metal at the rear end of the PH mounting channels.
.....the latest design has has a spring force reaction block mounted on a large aluminum angle that takes the place of the helper spring cover plates; this angle mounting plate also screws to the side of the roof channels in two places for further robustness.
In this design all of the spring load is reacted by the 5 screws that fasten the aluminum mounting angle to the channel......I hope this is clear....
This allows me to crank up the spring load at the end of the travel without overloading the end pocket of the channel which is just bent steel.
The aluminum channel mounts flush with the top of the channel so it's lower profile than the stock SMB helper spring cover plates as well.
I'm still using the 1176 lbs/in die springs from Mcmaster, and I can add or subtract washers under the spring to change spring preload. Each washer is .060" thick and changes the spring load by 70 lbs per side.
This configuration works the best so far (as expected!)..but I'd still like more spring load at the very end of travel when the roof is down.
I have 3 solar panels and some Yakima crossbars on the roof and can raise the roof with one arm now, but again..more spring help when the roof is first lifting off would be welcome.