multimode cb radios the older models

hi i am looking for information on converting older multimode cb rigs to use on 28 30 mhz  10 meter  band what whould you recomend thanks for looking stay safe do radio 73s paul m0kbd

Alot of older multimodes already go to 28 /30mhz 10m without mods ,,I have just sold one a Midland 8001xt which actually goes from 25mhz to 30 mhz , also you have the original old President Lincoln (not the Lincoln 2) that is actually a 10 m radio which was converted into a 11m radio which goes up to about 29 mhz ,  original old President Jackson goes from 26mhz to the higher end of 28mhz  there is many more if you actually research, so really you have a lot of older multimodes already for your needs without messing about try to covert one unless that's your thing, but you might find it harder going down that route as parts for older multimodes or even older ordinary CB is becoming scarce now .