TE - that was an interesting question, so I did a quick seach of the Golf Illustrated articles leading up to the '29 Amateur. Here are three articles from G. O. West. (They are now the only things I know about the original PB.) In the first, there doesn't seem to have been much wrong with Pebble, except for the 5th hole; by the last, we learn that the course has been lengthened and many of the greens have been re-done:
From mid 1927:
"It is now taken for granted that the 1929 National Amateur will be played over the picturesque Pebble Beach links. Nothing official has been released, but the insiders seem to think it is practically settled. The course as it now stands is a championship layout, but it is said that at least $30,000 will be spent in bringing it up to a top-notch condition. One expectation is that the Canary Cottage fifth hole will be completely changed. Otherwise the course will be hard to improve except in minor matters."
From early-1928:
"The writer has talked with leading golfers from all sections of the coast since Pebble Beach was selected by the U.S.G.A. for the 1929 National Amateur and he finds the election universally popular. All agree that the scenic links along Carmel Bay can be put into satisfactory championship condition with the expenditure of even a less amount than the Del Monte Properties Company has already agreed to expend. Nearly every one has declared that the second nine with the exception of adding a trap or two, could hardly be improved. The reconstruction of the course for the championship is in the hands of the following committee: Robert Hunter, Chandler Egan and Roger Lapham, the latter acting as chairman."
From mid 1928:
"Speaking of Pebble Beach, the making over of the links is completed and the fifteen months nursing period has begun. The greens, practically all of which are made over, have been carefully seeded to Cocoos Bent, the new grass which has proven so remarkably successful—at least on the Pacific Coast. They will be given their first important test next September when the California championship is held, and a year later are expected to be in the finest possible condition. The new course is 6705 yards long, the old course was 6480. The holes are better balanced than they formerly were, only seven of them remaining the same length as before."