Limit Excerpt Length of Specific Plugins? (Pinboard)

Hi there,

I’m trying to limit the excerpt length of the “Pinboard” on the bototm half of the target page (listed below). In the case of the website, each Project displayed is classed as “pin-board-pin-text” and “entry-content”, and is pulling any posts categorized as either “current projects” or “past projects”.

Is there a way to truncate the descriptions on these without just attacking the other excerpt lengths?

I’m a php newby but am reading hard and trying to come up with solutions… or at least get my head around the vocab! Any help would be very welcome, I’m doing this site for free for a charity and would love to give them a good end-product ??

Target Site:
https://greening.honestmeans.co.nz/homebeta/

EDIT: Don’t mind if limiting by # of words or by # of characters, but if there is a fix for both, words would be preferable.