Trim silva.bacteria.fasta to V3-V4 region

Hi guys,
Which start and end point should I use to trim the reference to V3-V4 region? Is there a map table or something?
I’v tried to use pcr.seqs with V3-V4 primers but failed due to the gaps.
Or maybe I can remove all the gaps, trim it to V3-V4 region, and align it to something to get the gaps back?

May be you are looking for this…

Thanks, it’s helpful.