78 k5 Blazer 2WD oil pan drop

[Flmarine71]

I need to replace my front and rear main seal. I have not done either of these before. My 1978 light duty truck service manual outlines procedure for dropping oil pan and it does not mention the need to jack engine up for clearance- just remove dipstick tube, exhaust crossover pipe and starter brace. I have read many posts here on different year trucks that recommend either jack up motor or remove it completely to do this job. Are there certain years/setups that clearance requires this or can anyone comment on 78 2wd with stock 350 & TH350? Thanks.