The MRP G2 is like any other backplate, one for ISCG and one for ISCG 05. There isn't really enough room between ISCG and ISCG 05 diameters to have the material needed to drill 3 more holes and make it fit. Your best option would be to buy just a new backplate.
you guys might be able to get away with drilling one but unless you have a mill you arent going to drill out slots so rotating the guide is out of the question. i say just get a new back plate, and in the case of the lg1 just get a new one so that you have all the adjustment that you need. that is just my opinion.