I've been mixing my own brew for the 87, though I don't run it to often. I've been mixing 11 oz of Power Service, 8 oz of 2 cycle and add it to a full tank (20 gallons of ULSD). Passed the snap-throttle emissions test with its 22 yr old injectors and appears to run a little quieter than the day I picked it up.
2012 Chevy 2500HD ECSB, 6.0L gas, auto, 4x4, LT
2003 F450, 7.3L PSD, 6 spd stick, 2wd, dump truck
1983 GMC K2500 pickup - working on a Cummins 5.9L swap
1987 GMC K3500 Dump, 6.2L diesel, TH400 auto - project plow truck