they will not only conduct eye test but full body medical checkup from particular clinic approved by marine department before u entering alam.
btw, there is nothing to cheat, for academics, u need to show them ur hard copy..
for weight, may be u can cheat for ~ 5 kg...that's all..
alam's selection process is more stages than PUO,
PUO has very low requirement, they choose for non-colour blind n passed all the core subjects in spm ..even if u get D for english, u will be called for interview.
CGPA 1.0 to pass overall semester.
for ALAM, u need at least C6 in spm to begin with, technical subject is like engineering drawing or some kinds of SMK Teknik courses subjects,
this year the sponsor's requirement(except bumi armada, jpa, felda..) is 3.0 of CGPA, 1.7CGPA for alam itself to pass overall semester.
if u failed add math in spm, i suggest u take nautical studies or PUO's marine engineering...alam marine eng i think is way too tough for u..