I’d posted this over in the classic forum thinking those guys might be more familiar with the bike , but didn’t get any suggestions.
Will Serfas Drifters 29x2.0 tires fit on my 1993 Schwinn Crosscut?
I have 700x38’s on it now and want bigger and it looks like there’s still room left with the 38’s . I’ve read the 29x2 are like 700x50mm .
After doing some more researching, I got worried and tried to cancel my order but was told they were in shipping .
When they get here , should I try them or refuse them and send them back if I can catch the delivery person ?

Best way is to measure the clearance your current tires have to the frame, I like using allen wrenches for this. In theory, 50mm tires would need 12mm extra vertically, and 6mm extra on each side. Tires vary a lot so I would make sure you have a few millimeters to spare in all directions.

12mm is 1/2".

Tire sizing between brands can be a bit iffy. Sometimes within the same brand.

I would be somewhat surprised if a '90s hybrid would fit 29X2 tires, but stranger things have happened.

I have 700 x 40s (Michelin City/Protek with smooth tread) on my '93 Trek 750 and '92 Schwinn Crisscross (probably similar to your Crosscut); I think that 50s MIGHT JUST fit but it would be close. Tires do not run true to size so comparing different brands is dicey.

They’re going to deliver them , I may as well try them .
I’ve tried three times to cancel them because they still haven’t shipped. My last two requests were totally ignored.
If they are too big , I’ll return them as I don’t own anything else that they might fit .