Furthest right Biden voters: Suburban ancestral republicans that were disgusted by Trump. Basically the guys from the Lincoln project.
Furthest left Trump voters: Maybe some South Florida Latinos that hate socialism and voted for Clinton in 2016. Said voter is represented in congress by Carlos Gimenez or Maria Elvira Salazar.
I don't think those South Florida Latinos would be particularly left.
They seem to hate socialism, but the congresspeople they elect seem to be some of the most liberal republicans in the caucus.
And Gimenez and Salazar don't seem to be in hot water for being "RINOs."