Good luck. Sometimes you just need patience to find the right thing at the right time.
My "race car" started out as a front damaged car from the auctions for $500 about 8 years ago (you can buy straight ones for less than this now), threw away the interior, stripped the insulation off the floor, spot welded the strut towers (the front LCA mounts are particularly bad on this model as they are cantilevered forwards off the bottom of the firewall only...), fitted rally upside-down coilovers & swaybars. Originally built to fit into a 1 make rally series which allowed no mods to brakes, engine, gearbox, ECU.
I took so long to build it that the rally series started to dwindle, so started modifying it. Bought a crashed 04 Elantra. Fitted the steering knuckles which allowed Mitsubishi EVO III front brakes, also EVO III (actually FTO) rear calipers and their mounting brackets on Elantra rear rotors to delete the rear drums. Mitsi hand brake cables & brake master bolted up directly. Found out from US forums that the front LSD to suit a USDM turbo 4wd Mitsi Eclipse fits the Elantra box, ordered a Quaife torsen, fitted it into the box myself & then fitted that onto the standard engine with some custom (mixed & matched off the shelf items) driveshafts to suit. The box bolted directly up to the engine, but the 2L & 1.5L flywheels have different bolt holes despite being identical in dimensions, so I got that redrilled & rebalanced. Fitted a bolt in cage, which required fitment of harnesses as the main hoop blocked the B pillar mounts.
Plans for this year are to finish installing the 2L Elantra engine from the wreck (which will give a nice 30% increase in power, and finally fit the racing seats I've had sitting around for years.
Kind of wish I'd sold it years ago though. The rear wheel arches are narrow, so I've had problems with the rear tyres either rubbing on the coilover spring, or catching on the outer guard (my new neighbour thought I'd converted it to RWD cos of the black rubber on the rear guards). I can't get it lower so that the handling is better, and Hyundai engines in the past haven't really been built around performance. A Mitsubishi Mirage is much more modifiable and had a racing model from Ralliart.