How to determine where to put shock mounts

[1989 comanche mj]

I have about a 5.5 inch lift on my Comanche, spring over with d35. Its a RE kit with longer shocks.  The brackets and spring perches on there aren't equal, I think they bolted everything up and started welding.  I don't have any confidence that the shock height was set right.

 

I have my 8.8 regeared and ready to go in.

 

Should I weld the perches on with the shocks in the middle of their travel at ride height?  Or weld them on at full extension with the axle at max droop?

 

I know the ideal way is with a fork lift measuring max up and down travel, but I don't have one, and don't have a way to flex it all the way up.