I know that if you haven't done the conversion, you think it's a few bent brackets, maybe a tunnel and some wiring.

Every bloody nut and bolt gets a workout. Diff, brakes, handbrake, suspension, steering, brake lines, fuel lines. etc etc.

You really gotta keep telling yourself the old saying 'you can't make a silk purse out of a sows ear'.

Keep some perspective, or it can quickly climb into many many thousands.