It's harder to turbocharge su's with a blowthrough setup than the webers(superior in that it allows you to use an intercooler), but it is possible to do a single draw-through setup by making a plenum with a single entry to replace your su's on the manifold, and mounting your single su in front of the turbo. It's just so cheap and easy (junkyard/ebay shopping) to get the fuel injection stuff that it seems silly to do it with carbs anymore. Since nissan made the L28et so easy to swap parts from, you shouldn't have to fabricate too much to get it to work. However, using a draw through su would mean that you wouldn't have to change your fuel pump, but you would still need the turbo/manifold, oil feed/return lines-turbo or modified NA oil pan, and whatever adapter you would plan to used to mount the carb to the turbo as well as the associated plumbing. Somebody posted an ebay ad for an old system like this last week sometime, you should be able to find it if you search around. All said and done, if your goal is more for hp per $ than period correct/wow factor, your time and money would probably be better spent on getting the parts you need from a ZXT and using a Megasquirt ecu to control it than using the carb system.