OK, this is the best I can do to answer the question of “what do I need to make my F103 an F103GT?”

You will need the following:
1. 51242 - B Parts Bumper & Body posts
2. 51244 - F Parts Link Type Front A-arms
3. 51229 – T Parts (x2) Body Posts, Frt Axel Carriers, Wheel Hex’s etc
4. 51227 – R Parts Servo Mount, Plastic Diff Joint
5. Metal Parts Bag (contains: 51232 Rear Wheel Mount L, 51231 Rear Wheel Mount R, 51233 Diff joint, 4305371 Damper Mount, 3485036 Rear Shaft)
6. 4005112 – Chassis
7. 9400389 - Shaft Bag (contains: 50594 axel shafts x2, 980852 stainless shafts x2, 9808053 stainless shafts x2, 9808825 friction damper post, 9805502 F wheel axel x2, 9805525 friction damper pole)
8. 9400393 – Ball Connector Bag (this has the balls for the link type suspension and rear axel spacer)
9. 51088 – Urethane Bumper
10. Gear Bag – Contains: Diff Housing B, Diff Housing A, 70T Spur Gear and plastic bushing not used in the kit

I think this covers the basics that you’d need to work a conversion. Of course you’ll also need tires, wheels and a body.

Hope this helps.