If you wear the proper protection and don't weld everyday all day you should be fine. Most people who weld for a living should be capable of building you engine mounts, just as long you keep you part of the deal and design the parts properly. Find someone who will listen to how you wants your parts made, and so some research so you can tell him if you want a part brazed, MIG welded, Stick welded, fusioned, or spot welded together. Also if they have somewhat of a machine shop you can usually get better made parts, as the parts will be cut on milling machines, bandsaws, or plasma CAM machines.
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93 Thunderbird 5.0 HO
89 Firebird L03
95 F150 XL
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