Mortgage - Also a guarantor

CHJM123

All, 

First post hi. 

I am sadly in the position that me and my partner may be going separate ways, we own a lovely home but it looks like its coming to an end etc. 

Currently have about 20 months of a 5 year deal left so I will need to check what fees are but suspect going to be costly to get out early. 

I am currently also a guarantor on a family members mortgage, I am more than financially comfortable with earnings to effectively cover my own (in full) and his mortgage but I wondered how I might be viewed by banks trying to seek a sole mortgage for myself?

Credit score 999 etc with reasonable savings... all I hope might help make the gurantor element not such a issue? 

Anyone tried to get mortgage whilst acting as guarantor etc? 

Any comments or help appreciated. 
Chris