Honda frame compatibility?

Not sure if this is the perfect spot for this, but oh well.
Long story short, I have a cm250 engine, suspension, and wheels looking for a frame to live in. I've been cruising craigslist and eBay for a frame, and started looking for older twinstar (185/200) frames since the bottom ends of the engines are supposed to be the same. I found a 185 frame and noticed that it looks EXACTLY like my CB125 frame. I'm curious if the mounting holes are in the same spots. If so, I should theoretically be able to use any CB, CL, or XL frame between 100 and 185cc which would greatly expand my frame options. Especially since there is a 185 roller not far from me for a deal.
The only issue I can see would be with chain alignment, but that's something that offset sprockets could fix.
If anyone has a cm engine or frame they could measure the mounting holes on for me I'd appreciate it. Mine is down in California at my school storage unit, so I wouldn't be able to check it for a couple weeks. I'm going to take measurements on my CB125 frame the best I can without dropping the motor.
If anyone has experience with this or is willing to take some measurements please respond!

Still seeing if anyone could help me out and measure their cb100/125 frame for me... Looking for the measurements between the two back mounting bolts, and the distance from the back bolts to the front down tube. Thanks!

Here's the 250 frame for reference... Looks very similar to me.

Every engine you mentioned has the same bottom end bolt pattern as every frame you mentioned, as long as you have the motor mount brackets you'll be fine. The cm250 in an xl185 frame may require mods for the intake/carb setup, depending on what year it is. It will also be plenty strong for everything but the harshest of riders. If you are talking about a 185 twinstar frame, I have less experience with those but am still positive the motor will bolt in.

Awesome. They looked the same to me, but wasn't sure if there was a size difference or anything. I was planning on having to do mods on the intake setup, since the cm motors have the single carb with manifold set in the middle and the XL's have their intake port and carb off to the side.

Planning on checking these out this weekend. Plan would be to get one running for a quick flip, and use the roller for my 250 motor and such.
http://sfbay.craigslist.org/scz/mcy/5238758955.html
Also thinking about checking this out:
http://sfbay.craigslist.org/eby/mcy/5243871124.html
Not as big of an investment and a disc front brake However it is about an hour farther from me than the other two.
Also looking into a piston swap. I have a GS550 motor which I took apart, two of the pistons were frozen to the cylinders, but two look to be in pretty good shape. They're stamped ART, so not sure if they're aftermarket. Should be right around 56mm (stock 550) which would put me up to 261cc in the CM motor. Need to check if the pins are the same diameter and what the height difference from the pin is. Don't want to be hitting the head.

Update: Suzuki Pistons are stock. Also, wrist pin is bigger than the 250, and the crown is WAY taller. Not sure you can put anything more than 56mm in without having issues on sleeve thickness.

So that 125 is apparently a learner bike that was supposed to be destroyed... I asked him about the VIN and he didn't respond. Bummer, I'd like to have it as a street bike with the disc front and monoshock.