Doubt it, chequer plate is not really suitable as the surface tread markings catch onto things when travelling, and ally is a little soft and prone to damage for a skid plate.
Welding ally is the next problem, it requires specialised powered gun MIG welders, or TIG welding equipment which is expensive, and to weld ally it needs to be AC TIG and use argon gas, i have recently replaced mi AC/DC TIG and it cost well over £1000 for a small machine, this cost needs recouperating by industrial users.
Probably better using 4mm steel plate and cutting the individual pieces with an angle grinder and thin kerf slitting disc and tacking them together, fir into place to ensure fit, then fully weld; many people have MIG or stick welders and could do this for your budget.