Do you have a HP goal in mind, or are you happy with stock, or have you got your pump cranked up?
In my experience, under towing situations with a 5speed I loved my WH1C. I had my pump turned up quite a bit with the pin cut and Gov spring, and timing, along with the exhaust and removed intake filter box. For my application the WH1C was probably the best turbo, I had instant spooling, an MWE slot, and a 57MM compressor. With my settings and the wastegate not hooked up, My max boost was about 37-38PSI.
Your ultimate goal totally dictates what you require for a turbo. You can spend thousands of dollars trying to keep whats right for your application. Like I said before an automatic truck can run a 16CM exhaust housing the best, wheras a manual need something smaller like a 14 or 12. thats pretty much the constant answer. A STOCK 1st gen. needs nothing more then the exhaust side changed out to something smaller. Being a 92 u have the huge lag pig 21CM exhaust housing, and a 55mm Compressor. The 55MM compressor will work fine untill u really add the fuel, then compressor surge, and air flow becomes an issue.
Look into getting a 16 CM housing if your an auto, and a 14 if your manual. I loved my 12 for all around streetability, i used my truck for a DD/hotrod/occasional tow truck. The 14 is better suited for towing and highway driving because of its ability to flow more exhaust then the 12. The 12 adds some EGTs because of its small diameter making the exhaust flow restrictive. BUT you lose SOME of the quick spooling, but going from a 21 to anything from a 16-12CM housing is a HUGE gain.
350-450 Horse 1st gens require in the range of a 62-64MM compressor, I could refer you quite a few vendors but thats between 800- 2000 dollars,
250-350horse 1st gens require from 57-62MM compressors, less expencive options are here because of the lesser requirement of air.
Fill in the blanks and we can help, but we need to know some vital items, Transmission, rear, HP intentions (no money spent 1st gens can make from the stock 160HP to around 250HP with the twist of a some screws)
And intended DAILY usage, what percent of the time is it going to tow, I know u mentioned its going to tow, but how often, and how heavy.
Sorry its so long, but turbos need to be picked presicly for exacting specifications, or u just wasted HUNDREDS of dollars on the wrong piece of the puzzle. Turbos are almost a science.