Start with either a RG550 or RG570. You can pick one up for about $300 if you look around. I found a 2001 rg570 for $279 in almost mint condition in the summer. Its the guitar in the picture. If you buy everything in parts, youll spend twice as much. After you have the guitar, strip the paint and sand the sucker down. Next, cut your monkey grip and lions claw if you want it to look like a jem.
After you have done your woodworking, prime it, paint it, clear coat it and polish. After all thats done, you can add whatever hardware you want. This is what I did and it cost a total of about $500. I have 2 more pickups coming and mine will be done. You can do all this in a week if you want, or like me, Ive been doin things here and there. Heres a picture of what I did. I tried to make a PMC, but the colors came out dark. Im going to actually redo the paint when it warms up outside. Go to projectguitar.com for all the instructions on how to's. The easiest part was doin the woodworking.