1275 A+ it is.  The dizzy clamp and dipstick confirm.

Thank you all very much.  

ID is easy, once you know what to look for.

The ribs mentioned is one distinguishing feature on an A+. Other clues are the dipstick hole and method used for securing the distributor.

Pre A+ engines have a raised tube for the dipstick, A+ motors just have a hole in block casting which stick goes into directly. 

Pre A+ distributor uses a clamp around the foot of dizzy, has an addition removable boss for dizzy to slide into. The boss uses two 1/4" bolts to secure dizzy clamp. A+ has no boss, dizzy slides straight into block, and a fork type clamp that is secured with a single bolt.

Lastly, to check engine is indeed a 1275A+ and not a 998A+ check the frost plugs. 1275 have 5 frost plugs, 3 across front of block and two on side above clutch housing. 998 have 4 frost plugs, 3 across front of block and one on side above clutch housing.

I'm not sure what to call them but A+ has a network of reinforcing 'ribs' on the front of the block. Post a picture of the motor then there will be no doubt. 

I was able to secure a very nice 1275 motor complete with al the goodies to replace my 998.  I will be swapping these soon and do not know how to identify the motor.  Not sure how to differentiate between an A or A plus?  Want to have as many replacement parts on hand like hoses, mounts and other rubber bits prior to starting the work.

Also any helpful tips for removal and install.  Have done many Sprite and Triumph motors but this is first Mini swap.  

Thanks in advance.