Designing Kitchens and Bathrooms - Replacing Shower Stall

I am a reasonably experienced DIY guy. But I've never tackled a job like this before. I want to replace a one piece shower stall with a two piece replacement. Both are fiberglass. The original one is about 35 years old, with one handle that controls the temp and flow.

What is the overall difficulty of this task?
Will I have to do any plumbing like sweating joints?
Can it be refinished? It's only the color we don't really like, it's in good shape. If so what is the typical cost to refinish one of these professionally.

Thanks in advance. Love this site.
Jeff

Recoating a fiberglass shower can be hit/miss, depends on how good the locals doing it are. But 35 is pretty old for a plastic shower, showing any cracks??

Many of the 2 piece units I am familiar with are for new construction, and difficult to do for a remodel. The often bolt together at the joint. Kind of hard if there is drywall blocking the way. If you get a unit designed for remodel, they are not too difficult. Yes, there will likely be soldering involved. Don't try to reuse the old faucet.

Ok I think I'll leave this one to the professionals.