I know what you're saying, that 1-4 in a 4spd is comparable to 1-3 in a 5 spd.... but remember you are "losing" your first gear ratio (it's gone) and 5th is no longer useful.
Sure, you HAVE 1-4 available, but 1st gear will be much deeper. Know what i mean?
And no, the bigger, the tougher it is. It's exponential.

89 4Runner
3" BL, M/T locks, 33"bfg mt, bilstein, Kayline, tubebumper, toyotafiberglass panels
TBI: Elocker,3.4 w/ORS,b+b,S2Sstg2cams,arias pistons,P+P intake,TRDs/c,URDpullies+7th,downey headers,MAPECU2,WEGO WB, SupraMAF,walboro255,stg4clutch, EPaOo2 sim