My brain has gone on strike.
8a Weak person to dive right in (4) d?i? (drip)?
10d Bishop to wreck old chevrolet truck (5) b???n
12a (had) called for journey to Gateshead? (4) ???g
25d Flipping cakes, alternatively an Iveco truck (7) s?r?t?r
27a End of repairs for old truck (5) ?o?e?