Welcome !!
Since you have some experience with diesel engines then you'll probably be further ahead than a first timer...
Gauges first... . Pyro, Boost, Tach... in that order, for me anyway.
Then I'd do pump timing, set usually between 1. 45mm - 1. 50mm plunger lift, or 14. 5* and 15. 5* advance. You can go higher, in fact as high as 17* advance but I personally am not that daring since this is a daily driver for me and there is no imperical evidence of no damage resulting.
In terms of "cost effective" mods for performance, you should consider:
1) AFC adjustment
2) Full fuel adjustment
3) Starwheel adjustment
4) Smoke screw adjustment
5) High idle adjustment (governor) to about 2950 RPM.
All are "free" tweaks
Air in ~ air out are not free...
You need a better exhaust system for relief of backpressure, and a high flow air filter to improve air supply. This will allow more complete burning of the fuel you added above in the "free" section.
The 93 came with an 18. 5cm exhaust side turbo housing. It is a bit slow to spool up but is great if your an open highway/towing person.
I suggest either the 16cm or 14cm housing (both cheap if non-wastegated) for much faster spoolup. They can cause some higher EGT's if you tow heavy though so keep that in mind, particularly when you get into the smaller housing sizes like 14 and 12cm.
This is really a factor if you like the "WOT is the only way to go" theory.
The next in line is injectors. Is this cost effective??? Well, consider that it is the more costly of the ideas but also reduces pump strain a bit in the process. Since they flow more fuel naturally, you don't need to work the pump as hard to get the juice into the engine.
The pump adjustments, air in/out, and injectors will take a stock truck from around 13 psi boost to 26psi or more depending on settings. It will also take you into the max continuous operating temps pretty quick if you get crazy with settings (1250*F BTW)
At 1500*F you've got seconds ..... some people have more seconds than others

, but still, seconds.
BTW, one request if you wouldn't mind NWvintageagparts, when you post would you be good enough to use lower case instead of upper case. This allows you to use upper case as a means of emphasizing something when need be. Otherwise, its considered shouting in here.
That is, unless you have a vision problem in which case that can be accomodated.
Thank you.
Bob.