i'm not completely incorrect. don't assume yours is the only way.
first of all, he doesn't need new shocks in the front. 6gun offers knuckles machined down to accept 02+wrx width struts. i know. i have them.
(I still run D-specs.)
2nd. if you need new axles in the rear to use STi hubs w/ 5x114.3, then he could simply take my 2nd suggestion, which is to have some WRX hubs redrilled for 5x114.3 bolt circle and move the studs. assuming there is enuf room on the hub (only moving the bolt circle 7mm out, i'll bet its doable), then this would only necessitate removing and reinstalling the hubs from the knuckle, no more difficult than replacing a wheel bearing. all you're really doing is changing the bolt pattern on your hubs.
(did fix my incorrect info above, however, thanks for correcting me)