Does anyone know if a convertible top, and front and rear bumpers from a 1977 spider would work on a '75?

Before I get my car on the road, a couple things I need are to replace the ragtop and add some sort of bumpers (currently has none) and there's a local craigslist ad parting out a 1977 spider. Before I pull the trigger and buy some parts, I was wondering if anyone knows if they would be compatible with my car?

I just bought a new top for mine. The OE type was $250 and the "luxury" model $360 or so. According to the instructions, the top was modified in '79.

The bumpers were changed over the years. In '76 the US came up with "zero damage" requirements which was a drastic change from prior years on all car.

original parts from 1975 through 1978 1800 cars are the same except a few minor things. The top and the bumpers are the same