Well...

1) A conveyor belt is a big add on that will cost a lot to do correctly.
2) You'd need to rotate the piece to do a wheel arch. So a conveyor belt wouldn't work as you'd need a fairly complex motion.

Basically, the dimensions are too big for home 3D printing.

And, again, amount of time that it takes to CAD one of these pieces is pretty significant. How many hours is it worth to save $175? How much would you spend to have the ability to do that? Realistically, the kind of 3D printers that *might* be capable of replicating *this* piece start well north of $10k. (It might actually be pushing $100k.)

And don't forget that the 3D printed piece would require finishing after all this. For a one off piece, you'd probably be better off hand fabricating in fiberglass.

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