combining substitute and concatenate

I need to reverse the order of the first/last name as well as remove the space between names that have mac in them. So for instance cell C13 contains the name "Elanor Mac Gowan" would need to be changed to "MACGOWAN ELANOR" I also need to make the whole thing upper case

So far I have =UPPER(RIGHT(C13,(LEN(C13)-(FIND(" ",C13))))&" "&LEFT(C13,(FIND(" ",C13))))

Which reverses the names fine.

I also have =SUBSTITUTE(C13,"Mac ", "Mac") However I can't figure out how to merge the two..

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One possibility

=UPPER(TRIM(MID(REPT(SUBSTITUTE(C13," ","",2)&" ",2),FIND(" ",C13)+1,LEN(C13))))

or

=UPPER(SUBSTITUTE(REPLACE(C13,1,FIND(" ",C13),"")," ","")&" "&LEFT(C13,FIND(" ",C13)-1))