Manual Trim
Biggest challenge IMHO will be routing the manual trim cable through the fuselage and mounting the control in the cockpit. Lots of crawling in tight places after removing baggage compartment cover, seats, etc. Difficulty depends on how your plane was built (removable panels vs. riveted, etc.), but it will take some time in any case...
Don't forget changes in your wiring diagram...may be some second/third order effects if you have electric aileron trim, stick grip with coolie hats, etc.
Once you've got the cable mounted in the fuselage, you'll need to do some rework on the left elevator and trim tab. The manual trim cable mounts onto the E-615PP trim cover plate with the WD-415 trim cable anchor. This is the same E-615PP plate used to mount the electric trim servo, but your best bet is to replace it with a new one with the manual anchor since the brackets are totally different. The trim cover plate and the hole/reinforcing plate w/platenutes are the same for both manual and electric so once the assembly is put together it should screw right in once you've mounted the cable to the bracket.
The trim cable connects to the trim tab horns using an HW nylon clevis 1032 assembly. The E-717 (outboard trim tab horn) and E-718 (inboard trim tab horn) are cut differently for manual vs. electric trim (they are taller for manual trim to give more leverage) and must be replaced. Most builders rivet these onto the trim tab, but I've seen a couple RVs where they were mounted with screws. If you're able to remove the old trim tab horns without screwing up the trim tab itself you should be able to mount the new ones without too much trouble. Worst case: trim tab gets screwed up somehow and you end up making a new one.
The trim cable uses the same size snap bushing as the electric on the forward spar of the elevator, so no drilling is required; cable will pass through where the wires are now.
See DWG 4 for details, mounting distance for the trim cable bracket, etc.
Parts for all of this shouldn't be a big deal; check 'the list' on Van's website for current prices.
Good luck!
