landing gear install on that type of fuselage is quite simple. Check out
SPADTOTHEBONE.COM
4 pieces of 6"yard stick, 4 1/4-20 blindnuts with PLASTIC 1/4-20 bolts and your ready to go with an aluminum gear and some wheels of course. If you fly on grass I would recomend 3.5 "diameter wheels. A tail wheel is not totally needed but might be nice. recheck CG